The present invention relates to a copier of the type having optics which scans a document while moving in a longitudinal direction as viewed from the front or operating side of the copier.
Generally, a copier has a paper feed mechanism and a sheet or copy discharge mechanism at laterally opposite sides thereof as viewed from the side where one is expected to operate the copier, i.e. the operating side. For example, a paper cassette is loaded on the right-hand side of the copier while a copy tray is loaded on the left-hand side. After a toner image representative of a document which is laid on a glass platen has been transferred to a paper sheet that is fed from the paper cassette, the paper sheet or copy is driven out of the copier to the copy tray. Although the paper feeding and paper discharging directions may somewhat differ from one copier to another, the paper feed and paper discharge mechanisms are positioned on laterally opposite sides of the copier without exception. Such an arrangement stems from the fact that the relationship between a document and a copy is easy to set up when a reference document position defined on the glass platen and the initial optics position are coincident, in consideration of the relationship between the moving direction of the optics and photoconductive element and the paper feeding direction.
A problem with a copier having the above configuration is that it needs a large area for installation, i.e., the projective area of the copier body as measured in a plane plus the projective areas of the paper cassette and copy tray which protrude from opposite sides of the copier body. Further, an additional space is needed which is wide enough to allow access to paper cassette in the event of replacement. Eventually, the area necessary for the installation of the copier is far larger than the area which the copier body itself assumes, reducing the area available in an office for other various activities or other office automation equipment.
It is perferable, therefore, to reduce the exclusive area for the copier at least by designing it such that noting protrudes from the opposite sides thereof. This requires the paper feed mechanism to be provided on the front of the copier body, i.e., the operating side for the purpose of facilitating manipulations. Then, a paper transport path which extends from the operating side of the copier toward the rear of the copier is indispensable in relation to the paper discharge. When a copier having such a layout is implemented by conventional optics and developing and fixing arrangements, a photoconductive element is necessarily located in the vicinity of the operating side while the optics start scanning a document at the upstream side with respect to an intended direction of rotation of the photoconductive element. Stated another way, in the layout stated above, the optics begins scanning a document at the opposite side to the operating side, i.e., at the rear end of the copier. This in turn requires the reference position on the glass platen to be defined at the side opposite to the operating side. Such a reference position, however, would render the positioning of a document on the glass platen troublesome and inefficient. Especially, when a documnet in the form of a book is used, the positioning and copying work would be more thoublesome and even pressing it down would sometimes be difficult.